Dose-Response Characteristics of Spinal Bupivacaine in Volunteers: Clinical Implications for Ambulatory Anesthesia

Background: Small doses of bupivacaine may be a reasonable choice for spinal anesthesia for patients having ambulatory surgery. However, few dose-response data are available to guide the selection of reasonable doses of bupivacaine for different ambulatory procedures.

Methods: Eight volunteers per group were randomized to receive 3.75, 7.5, or 11.25 mg of 0.75% bupivacaine with 8.25% dextrose in a double-blind manner. Sensory block was assessed with pinprick, transcutaneous electrical stimulation equivalent to surgical incision at the ankle, knee, pubis, and umbilicus, and with duration of tolerance to pneumatic thigh tourniquet. Motor block at the quadriceps and gastrocnemius muscles was assessed with isometric force dynamometry. Times until recovery from spinal anesthesia were recorded. Dose-response relationships were determined by linear regressions. Mean (95% confidence intervals) for durations of sensory and motor block per milligram of bupivacaine administered were calculated from linear regressions.

Results: Significant dose-response relationships (P < 0.006) were determined for sensory block, motor block, and time until recovery (R from 0.6 to 0.9). Within the range of doses studied, each additional milligram of bupivacaine was associated with an increase in duration of tolerance to transcutaneous electrical stimulation of 10 (7 to 13) min, an increase in tolerance to tourniquet of 7 (2 to 11) min, an increase in duration of motor block of 8 (5 to 12) min, and an increase in time until recovery of 21 (17 to 25) min.     

Balloon Catheter with Extra-amniotic Saline Instillation: a Method of Induction in Pregnancies at 41 or More Gestational Weeks

Summary: One hundred five women with a documented pregnancy of 41 weeks' gestation or more, admitted for induction of labour by balloon catheter with extra-amniotic saline instillation, were retrospectively compared to 196 women admitted in spontaneous labour at the same gestational age, with regard to mode of delivery. The success rate of the induction group was 97.1%. The mode of delivery did not differ significantly between the 2 groups. The Caesarean section rates were 11.4% in the induction group versus 9.7% in the spontaneous group. The mode of delivery after induction of labour by balloon catheter with extra-amniotic saline instillation and simultaneously commenced intravenous oxytocin infusion, in pregnancies of 41 weeks or more, is similar to that of spontaneous deliveries at the same gestational age.     

Event-related potential correlates of functional hearing loss: Reduced P3 amplitude with preserved Nl and N2 components in a unilateral case

Abstract A female patient exhibiting functional hearing loss in her left ear demonstrated reduced amplitude of P3 component in event-related potentials (ERP) to left monaural stimulation, with preserved N1 and N2 components to stimulation of either ear. This result suggested that stimuli in the affected ear were conducted successfully up to the auditory cortex but that further processing in higher brain regions was 'repressed'. Event-related potential examination for such hysterical disorders could be useful in clarifying their brain mechanism and offer a useful diagnostic clue to its nature.     

The information needs of women newly diagnosed with breast cancer

Nurses can play a key role in patient education, including providing patients with useful and approrate information Rather than focusing on the process of education or information giving by nurses, this study places emphasis on the content of that information by taking the patients'perspective and asking the patients themselves what particular types of information are perceived as important at a specific point in time The aim of the study was to explore what particular types of information were important to women newly diagnosed with breast cancer, to enable nurses and other health care professionals to utilize their time as effectively as possible and provide a high-quality service to individuals in their care Women with breast cancer (a mean of 2 5 weeks from diagnosis) were interviewed and asked to compare items of information The items of information were presented m pairs and the women stated a preference for one item in that pan- Thirty-six pairs were presented in total The analysis involved the use of a Thurstone scaling model, which allowed rank ordermgs, or profiles of information needs, to be developed, reflecting the perceived importance of each item Information about the likelihood of cure, the spread of the disease and treatment options were perceived as the most important items of information at the tune of diagnosis Other information needs, in order of descending priority, included information about the risk to family, side-effects     

Alcohol Use among Subcritically Injured Emergency Department Patients

Objectives: To determine the incidence of alcohol use in subcritically injured patients presenting to the ED, by using a saliva alcohol test (SAT) at ED triage during the ED initial assessment; to compare the incidence of alcohol use revealed by the SAT with documentation of alcohol use by ED nurses and emergency physicians (EPs) blinded to the SAT results; and to describe the demographics of the SAT-positive, subcritically injured population.
Methods: A blinded, prospective, observational evaluation of ED patients presenting with subcritical injuries was performed. The patients were tested for alcohol use with an SAT, and a subsequent record review was conducted for extraction of demographic data and evidence of documentation of alcohol use by ED nurses and EPs blinded to the SAT results.
Results: During the study. 791 subcritically injured patients had SATs performed. Twenty-one percent of these patients were found to be alcohol-positive by SAT. Either the ED nurse or the EP documented a clinical impression of alcohol use for 52% of the SAT-positive patients. There were higher SAT-positive rates among men (24%), victims of assault (47%), and patients arriving at night (41%).
Conclusions: While the SAT identified 21% of the subcritically injured patient population as alcohol-positive, ED nurse and EP documentation did not identify half of these alcohol-positive patients. Many of these patients may be at risk for additional injuries related to their drinking behavior.     

Postpemphigus acanthomata: a sign of clinical activity?

Background Pemphigus is a group of vesiculobullous disorders in which the blisters usually heal with hyper- or hypopigmentation. The appearance of acanthomata at sites of previous blisters has been noted in some cases. Methods All cases of pemphigus admitted to the Madras Medical College hospitals during a 2-year period from March 1993 to March 1995 were taken into the study and screened for the presence of acanthomata. Results Fifty-two cases of pemphigus were identified, 47 of pemphigus vulgaris and five of pemphigus foliaceus; and of these 13 developed acanthomata when the blisters healed. Ten of these cases were of pemphigus vulgaris and three were of pemphigus foliaceus; biopsy of these lesions showed hyperkeratosis, acanthosis, papillomatosis, and intraepidermal clefting. Immunofluorescence carried out in two of these acanthomata also showed intercellular fluorescence. Conclusions The occurrence of acanthomata in healed lesions of pemphigus is not uncommon; because histopathologic and immunofluorescence evidence of disease activity is present, cases of this sort require careful follow-up.     

Early detection of myocardial contusion and its complications in patients with blunt trauma

Myocardial contusion remains an elusive clinical entity, which consumes a disproportionate amount of scarce and expensive critical care resources for the purpose of cardiac monitoring. This study attempts to define a group of patients at high risk who can be identified from the available data present at the time of admission. All patients admitted with the suspicion of a myocardial contusion over a 3-year period were retrospectively studied. The records were examined for history, physical findings, electrocardiographic (ECG) results, creatine kinase levels, Injury Severity Score (ISS), and echocardiographic findings. A diagnosis of a myocardial contusion was made if patients had an ECG consistent with acute injury, increased creatine kinase-MB, or an abnormal echocardiogram consistent with acute injury. Patients were stratified into two groups: Group 1 patients satisfied the criteria for a myocardial contusion and Group 2 patients lacked sufficient evidence to substantiate this diagnosis. The records were then examined for the presence of factors available in the emergency room that might be predictive of a myocardial contusion or its complications. A total of 88 patients were evaluated; 27 of these were found to have a myocardial contusion (Group 1) with 61 patients placed in Group 2 (no myocardial contusion). Group 1 patients had an abnormal admission ECG (p less than 0.05), and an ISS greater than or equal to 10 (p less than 0.05). Multivariate analysis identified two factors predictive of a myocardial contusion: an abnormal ECG and an ISS greater than 10. When these two predictors were absent, the probability of a myocardial contusion was 1%. No predictors of a complication of a myocardial contusion were identified. These data suggest that a combination of easily obtained variables in the emergency department can be used to select a patient population at high risk for myocardial contusion. Prospective evaluation of these variables is necessary.     

Flexor digitorum profundus tendongrafting (extrasynovial donor tendons)

Although the prevalence of flexor tendon grafting has decreased since the early part of this century, the technique isstill an important part of a hand surgeons armamentarium. Primary and staged flexor tendon grafting are appropriate techniques used to restore digital function after failed or neglected repairs. Appropriate patient selection, meticulous reconstructive techniques, and respect for basic biological principles of healing and repair are essential elements for successful tendon grafting.